When/how often is it advisable to change the main spring in a SW revolver? Standard and reduced power. Appreciate the answers of you real Smithsmiths!

I wouldn't touch it, unless there were ftf’s (light strikes) or it broke. It's not like the mainspring on an autoloading pistol.

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"I also cook."

Count carefully. At 398,940 cycles it is imperative that the mainstring be changed.

Seriously, I agree with s&wchad-don't change it unless there is an indication of a problem.

I HAVE OVER 100K THRU MY S&W PPC REVOLVER AND NEVER HAVE NEEDED TO CHANGE IT.JP

You should have a couple extra hammer springs just because stuff does happen but in 42 years and hundreds of thousands of rounds I've never needed one of my "spares."

I think you have confused the mainstring with the timing belt which should be changed at the designated interval. Older Smiths have timing chains and need not be changed.

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Still Running Against the Wind

have never had the need to change one

I hear if you don't change it every 25000 trigger strokes it will snap, and then the valves will hit the pistons and trash the whole thing. Or something like that.

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Pisgah

All this can be avoided by simply swapping out the fetzer valve and flap-jack wingnut, and switching over to a full synthetic lube.

The only one I have ever changed was from a Trapper Spring Kit, and it was installed in a M-57 and broke in half during a match. I have never trusted non-factory springs since.

When/if it ever break's.

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H Richard
SWCA1967 SWHF244

I had to replace one on a 60+ year old pre model 14 it broke on its own. I also had to tighten the strain screw on a M-28 it needed a half turn after I noted two FTF over time. I figure as long as you take the grips and side plate off every now and then to clean and oil the areas nothing else is needed. If you have allot of old guns or if you like to shoot thousands of rounds through them you can keep a spare put away for that special day.

I have a few extras Mainsprings in my Sping Box & have never worn or broke any.
The ones I have came from perfectly good revolvers that got Wolff or JM springs & removed them marked them as which revolver & serial # they came from & put them away..

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MightShowYouHisSmith&Wesson